Re: [boost] [Function][Bind] Re: "Smallbufferoptimization"forboost::function?

From: Alex Besogonov (cyberax_at_[hidden])
Date: 2006-01-15 12:32:26

Edward Diener wrote:
> I would be careful using FastDelegate as an adjunct to Boost 
> function/bind. It is very dependent on knowledge of compiler member 
> function pointer sizes and uses "hacks" based on that knowledge to 
> achieve its speed. Boost should try to stay clear of low-level compiler 
> dependent knowledge whenever it can, sacrificing a little extra speed 
> for greater stability.
Boost already has a lots of compiler-specific hacks and kludges (see MPL 
or TYPEOF/FOREACH). There's nothing inherently wrong in a good hack if 
it is protected by #ifdef's and there's a fallback implementation for 
unsupported platforms.

> Of course if it is an optional choice for 
> end-users, then it is more understandable but even then end-users should 
> be duly notified of the issues involved. This is not in any way a 
> putdown of FastDelegate but Boost function/bind is richer in 
> functionality and therefore pays the price of being slower. Of course 
> speed is important but not if it means less stability of implementation.
SBO already gives 10x speed boost to Boost.bind :) It's performance is 
quite acceptable now.

-- 
With respect,
             Alex Besogonov (cyberax_at_[hidden])